Evaporator plates



United States Patent O EVAPORATOR PLATES Herman W. Kleist, Hollywood, lll., assignor to Dole Refrigerating Company, Chicago, lll., a corporation of Illinois Application August 11, 1953, Serial No. 373,584

2 Claims. (Cl. 62-126) This invention relates to an improvement in cold plates used in refrigeration and has for one purpose to provide lan improved evaporator in plate orm, for use in refrigerating units of various kinds.

Another purpose is to provide such a plate or evaporator in which an improved heat exchange relation is maintained between an outer housing and -a coil within the housing.

Another purpose is to provide such a plate in which the coil or parts of the coil are in heat exchange relation with the peripheral wall of such a plate throughout substantially the entire periphery of the plate.

Another purpose is to provide an evaporator plate in which a rectangular coil constitutes a iirm internal reinforcement for the plate.

Other purposes will appear from time to time in th course of the specication and claims.

The invention is more .or less diagrammatically illustrated in the accompanying drawings, in which:

Figure 1 is a plan view with parts broken away and parts in section.

Figure 2 is a section on an enlarged scale on the line 2--2 in Figure 1. g

Like parts are indicated by like symbols throughout the specication and drawings.

Referring to the drawings, 1 indicates a side sheet or plate side wall and 2 indicates a parallel side sheet or plate side wall, spaced away from the wall 1 by anges 3 which constitute a peripheral or circumferential connecting wall between the side walls 1 and 2. 4 indicates overlapping engaging wall portions which surround the plate. It will be understood that the above described plate structure is welded or otherwise connected to form a Igas tight container. As will be clear trom Figures 1 and 2, the space rwithin the plate thus formed is rectangular with the circumferential wall 3 generally perpendicular to the plate side walls 1 and 2. Within the housing thus formed I position a coil generally indicated at 5. The coil is preferably formed of rectangular tubing and is in the form of a plurality of parallel and generally rectangular lengths connected together by suitable bends or connections 6. If desired, internal spacers 7 may be employed, preferably of sheet metal.

In the particular coil arrangement shown herein I provide an inlet ltting 8 to which a volatile refrigerant may be delivered through a suitable supply pipe 9. From the fitting 8 extends an initial stretch or length of tubing 10 which connects by an angle element 11 to a second tubing length 12. The length 12 is connected by an angle portion or bend 13 to a tubing length 14. The tubing lengths 10, 12 and 14 preferably abut or closely approach three sides or lengths of the circumferential wall 3. The space within the plate, between the tube lengths 10 and 14, as shown in Figure 1 is occupied by a plurality of parallel and equally spaced rectilinear ltube lengths 15 connected by 180 degree bends or connections 6. The final tube length 15 terminates in a tlange or bend 16 which connects to a tube length 17 preferably in heat exchange relation with the last side or end of the circumferential wall 3 at the end of the plate opposite the tube lmth 12. This tnal tube length 11 terminates in m Patented May 7, 1957 'ice tion of parts without departing 4from the spirit of my invention. I, therefore, wish my description and drawings to 'be taken as in a .broad sense illustrative or diagrammatic, rather than as limiting me to the precise details of my disclosure.

The use land operation of my invention are as follows:

I illustrate herein a plate or evaporator particularly adapted for use in mechanical refrigeration systems in which a volatile refrigerant is ev-aporated. I find it preferable .to draw the side plates 1 and 2 against the opposed plane surfaces of the coil 5 by withdrawing air from the interior of the plate. As a result of such withdrawal, the pressure within the plate is less than atmospheric, and the excess atmospheric pressure serves to urge the side plate walls firmly against the rectangular coil in proper heat transfer relationship. By providing la. rectangular coil portion about each side of the peripheral wall 3, I maintain an advantageous heat exchange relationship about the periphery of the plate, land also in effect provide -a circumferential structural reinforcement. It will he observed from Figure 1 that I provide evaporator tube sections or lengths which abut the inner surface of all four sides of the circumferential wall 3.

If found advantageous, I may partially lill the space within the plate and about the coil 5 by a suitable eutectic. Whereas l have shown a coil and plate in which the exterior diameter of the coil determines the space between the two side walls, I may also employ a thicker or deeper plate, in connection with the employment of a plurality of coils or of depths of coil or in connection with suitable spacing means.

I claim:

1. ln a cold plate evaporator, a pair of plane generally parallel side walls connected by marginal walls around their peripheral edges in a ygenerally gas tight relation to dene a sealed generally rectangular chamber, and a continuous tube pattern conlined in the chamber adapted to contain and circulate a refrigerant, including a plate edge supporting and abutting, exure resisting outer frame composed of generally rectilinear tube lengths interconnected by internal right angle smooth bends, and an interior sinuous tube bodycomposed of generally parallel rectilinear tube lengths interconnected by integral smooth approximately bends, inlet and outlet connections for thetube pattern extending through the marginal walls for connection to la refrigerating unit, all of the tube lengths and -bends being substantially uniform cross section rectangular tubing and having at sides in surface contact with both plates throughout said lengths, the tube :lengths of the outer frame being liush against and in metal to metal contact with the marginal Walls on all four sides, and means for maintaining a sub-atmospheric pressure in the chamber about the tube pattern.

2. The structure of claim l further characterized in that -a eutectic partly fills the chamber about the tube pattern.

References Cited in the tile of this patent UNITED STATES PATENTS 

